Constant prime rapid recovery pump



Dec. 18, 1962 R. F. COSTELLO ETAL 3,

CONSTANT PRIME RAPID RECOVERY PUMP Filed March 1, 1961 2 Sheets-Sheet l 35 4H 24 a4 k 3 l 5 I FIG. 1

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INVENTORJ. Raymond F. Costello Fl 6 2 By & FranK OBvx'un M 9M5 Attorney FIG.5

Dec. 18, 1962 R. F. COSTELLO ETAL 3,

CONSTANT PRIME RAPID RECOVERY PUMP Filed March 1, 1961 2 Sheets-Sheet 2 INVENTOR5. Raymond F. Costello M .SMw

Attorney United States Patent Gfifice Patented Dec. 18, 1 962 3 058 S02 CONSTANT PRIME harm nacovnnr PUMP Raymond F. Costello, 1040 NE. 105th St., and Frank glBrian, 10610 NE. th Place, both of Miami Shores,

Filed Mar. 1, 1961, Ser. No. 92,492 2 Claims. (Cl. 103-113) This invention relates to centrifugal pumps and is directed particularly to improvements in the construction of moderate-pressure, volume-delivery centrifugal pumps.

The principal object of the invention is to provide a high volume, moderate pressure pump with greatly improved recovery action.

Another object of the invention is to provide a centrifugal pump of the character described including a diffusion chamber within the pump housing and communicating through a feeder opening with the inlet passageway to the pump impeller, the diameter of the feeder opening being about 3% of the impeller diameter.

Yet another object of the invention is to provide a centrifugal pump of the above nature which develops a vacuum at the intake port more quickly than in known centrifugal pumps of the same type having no feeder opening, or having a jet acting in conjunction with a venturi or increasing pressure, whereby recovery, even under conditions of severe intake line leak-age, will ordinarily be made in a matter of seconds.

Still another object of the invention is to provide a centrifugal pump of the above nature including a pressure actuated feeder valve in the feeder opening operative to close automatically immediately upon recovery of prime, thereby achieving maximum rapid prime efficiency with no loss in static pressure head.

Other objects, features and advantages of the invention will be apparent from the following description when read with reference to the accompanying drawings.

In the drawings, wherein like reference numbers denote corresponding parts throughout the several views:

FIG. 1 is an elevational view of a centrifugal pump embodyin gthe invention, with the pump housing shown in vertical cross-section and with a portion of the pump motor broken away.

FIG. 2 is an end view of the pump shown in FIG. 1,

FIG. 3 is a vertical cross-sectional view taken along the line 33 of FIG. 1 in the direction of the arrows.

FIG. 4 is a vertical cross-sectional view of FIG. 1 taken along the line 4-4 thereof in the direction of the arrows,

FIG. 5 is a View similar to FIG. 1 illustrating a modification of the invention utilizing a pressure actuated feeder in the feeder opening,

FIG. 6 is a transverse cross-sectional View, taken along the line 6--6 of FIG. 5 in the direction of the arrows, and showing on an enlarged scale the construction of the pressure actuated valve,

FIG. 7 is an end view of the feeder valve, taken in the direction of the arrows 7'--7 in FIG. 6,

FIG. 8 is a vertical cross-sectional view taken along the line 8-8 of FIG. 6 in the direction of the arrows, and

FIG. 9 is a vertical cross-sectional view taken along the line 9-9 of FIG. 6 in the direction of the arrows.

Referring now in detail to the drawings, and considering first the embodiment of the invention illustrated in FIGS. 1 through 4, 1i) designates a pump housing, which may be case of metal, for example, or molded of a tough, synthetic plastic. The pump housing '10 is formed at its inner or impeller end with ashort, circular projecting face 'portion 11 which fits or locates in a complementary recess '12 of a drive motor 13 (partially shown). The pump housing may be attached to the motor 13 as by machine screws 14 extending into tapped holes 15 provided in slightly projecting wing portions or bosses -16 integrally The pump housing 10 is generally cylindricalin shape at its inner or-impeller end and isqformed, inwardly-of the face portion 11 thereof, with a coaxial impeller chamber 17 defined by a frusto-conical wall portion 18 flaring into a coaxial cylindrical impeller bearing portion 19. ,Integrally formed with the bearing portion 19 of the impeller chamber 17 is a coaxial tubular wall portion 20-of1decreased diameter defining an impeller inletgpassageway or volute 21.

As illustrated in FIGS. 2 and 4, the front end of'the pump housing 10 is of reduced size, and is formed with an interior vertical wall portion '22, which, together with the wall portion 18 and the outer surface of the tubularwall portion 20, defines a large, substantially annular. difiusion chamber 23. v

The outer end of-the tubular wall portion,20 of the, pump housing 10 is joined with the interior vertical wall portion 22 thereof and communicates with-a pump input or vacuum chamber 24 defined by said vertical wall portion and the outer end wall portion 25 of said pump housing. The pump housing 10 is further formed witha vertical dividing wall portion 26 in vertically spacedrelation between the vertical wall portion 22 and the outer end Wall portion 25 thereof, which separates the vacuum chamber 24from the diffusion chamber 23. An opening 27 is formed at the lower end of the vertical wall portion 22 of the pump housing 10 communicating between the diffusion chamber 23 and a recirculation passageway 28 extending up between the dividing wall portion 25, and the outer end wall portion 25 of the said pump housing. vA feeder opening 29 is bored in the dividing wall portion 26 of the pump housing 10, the diameter of which is approximately 3 percent of the total diameter oflthe impeller 37 (hereinbelow more fully described) and approximately 7 percent of the internal diameter of the inlet passageway 21. The internal diameter of the inlet passageway 21 is thus substantially 43% of the total diameter of theimpeller 37. The outer end wall portion 25 of the pump housing 10 is provided, near its upper end, with a tapped opening or port 30 for connection of an input line 31 coming from a well or other fluid supply source. A tapped outlet opening or port 34 is provided inthe top of the pump housing :10 for connection of anroutlet or delivery line 35.

As illustrated in FIGS. 1 and 3, the pump housing 10 is preferably formed at each side with internal, horizontal baffle fins 36 extending between thefrusto-conical .wall portion 18 and the vertical wall portionZZ thereof, which assist in the separation oftrapped air in the water being recirculated during recovery, as is hereinbelow more fully described.

- Disposed for rotary motion in the impeller chamber 17, is a centrifugal impeller 37 ofqusual construction which is fixed to the output shaft of; the .drive motor 13. As illustrated in FIG. 3, the faceportionllof the pump housing 10 is formed witha pair of, diametrically opposed arcuate through openings 38 whichcommunicate at one end with the periphery of the impeller chamber 17 through entrance passageways 39.

In operation, rotation of the-centrifugal impeller37 in the direction of the arrow shown in FIG. 3r=will cause fluid in the pump drawn through the inlet passageway .21 to be peripherally expelledand'pass through the entrance passageways 39 and openings 38 into the diffusion chamber 23. The tumultuous flow of water through the armate openings 38 falls into the diffusion chamber 23 where entrapped air separates and rises to the1.surface,,aided .in the separating action'by. the bafile fins 36. Assuming that continuous flow is lost, and that the water level in'the 3 pump is at the level illustrated in FIG. 1, i.e., the level of trapped water in the housing, operation of the pump will circulate a stream of water through the feeder opening 29 in the wall portion 26. Since the inlet passageway 21 leading to the impeller also communicates with the pump input or vacuum chamber 24, air will be continually drawn into and entrapped in the recirculation water flow to rapidly build up a strong vacuum in the input line, which results in positive, rapid recovery.

It has'been determined experimentally that the diameter of the recirculation opening 29 must be approximately seven percent of the diameter of the inlet passageway 21 and three percent of the outer diameter of the impeller 31 to achieve rapid recovery or priming action. It was found that with such a size ratio, the outlet pressure or static head developed by the pump when in operation, i.e., the pressure developed in the diffusion chamber 23,is not significantly less than if the feeder opening 29 were entirely eliminated. As heretofore much attention-had been given to keeping to an absolute minimum any leakage between the outlet and inlet chambers in the designing of centrifugal pump housings, the abovedescribed results in operation due to the feeder opening 29 were most unexpected. When the size of the feeder opening 29 is increased much beyond the above described ratios, the static head of outlet pressure falls off rapidly. Decreasing the size of the opening 29 to a lesser ratio size greatly impairs the'rapidity of recovery action, to the point where recoveryis no better than in ordinary selfpriming pumps heretofore devised.

Though the feeder opening 29 is in axial alignment with the inlet passageway'21 in the embodiment illustrated, an opening of the same size could extend through the underside of the inlet tube 20 to provide the necessary communication between the diffusion chamber 23 and the inlet passageway 21, without substantial loss in recovery performance. The opening 29 is preferably where shown, however, at a location more remote from the impeller 37 so as to afiord more time for air separation in the diffusion chamber 23, and thereby producing positive recovery action.

e 'In the second form of the invention illustrated in FIGS. through 9, a pressure actuated feeder valve 40 is utilized in place of the feeder opening 29 in the wall portion 26 of the pump housing 10. The feeder valve 40 has a cylindrical body portion 41, which may be a plastic, for example, and which is press-fitted (or alternatively screwed) into a cylindrical opening 42 provided in the pump housing wall portion 26a. A threaded opening 32-and a plug 33 removably threaded therein is provided in the end wall portion 25a of the pump housing to provide access for inserting the feeder valve 40. The

body portion 41 of the feeder valve 40 is provided with an axial valve guide opening 43 and a plurality (four in the example illustrated) of end-to-end feeder flow openings 44 ar'cuately spaced about the central axis. An annular ridge 45 surrounding the flow openings 44 is formed at the outer end of the body portion 41 to provide a valve seat for a circular, resilient valve washer 46 of rubber, neoprene or plastic,-for example. The valve washer 46 is supported-on a valve guide bolt 47 extending axially therethrough and through a metal disk 46a against which said washer is'seated. The valve guide bolt 47.extends through a helical return spring 48, the axial opening 43 in the valve body portion'41, a helical spacer spring 49, and a disk-like metal pressure plate 50, the assembly being held together by a self-locking nut 51 threaded on the inner end of said guide bolt. The inner. ends of the helical springs 48, 49 are seated in countersunk recesses 52, 53 in the outer and inner ends, respectively of the'body portion 41 of the feeder valve 40.

In the operation of the embodiment of theinvention illustrated in FIGS. 5 through 9 water trapped in the pump will be recirculated through the comparatively large feeder flow openings 44 of the feeder valve 40. trapping chamber, a tubular conduit communicating at one end air from the input or vacuum chamber 24a as described above and discharging it through the outlet or delivery line 35. At the same time, pressure of the recirculation water against the pressure plate 50 of the feeder valve 40 will gradually move the valve washer 46 in the direction of the annular ridge or valve seat 45 against the force of the return spring 48. At the instant of full prime, the valve washer will snap fully closed practically instantaneously, and remain closed as long as the pump is operating, by virtue of the static head pressure being applied against the outer surface of the washer 48. Upon loss of prime, the return spring 48 will return the valve washer to open position again, ready for priming action again.

While there is described and illustrated herein only'one form in which the invention can conveniently be embodied in practice, it will. be understood that this embodiment is presented by way of example and not in a limiting sense. In short, the invention is limited only by the scope and spirit of the following claims.

What is claimed as new and for which it is desired to secure Letters Patent is:

l. A rapid prime centrifugal pump comprising, a pump housing, a first wall formed near one end of said housing and defining an impeller chamber at the outside of said wall, a centrifugal impeller rotatably disposed in said impeller chamber, a second wall in said housing spaced from the other side of said first wall, a tubular.

conduit extending between said first and second walls and defining an impeller inlet passageway, said first and second walls and said tubular conduit defining a recirculation chamber, a plurality of openings in said first wall outwardly of the periphery of said impeller and communicating between said impeller chamber and said recirculation chamber, a third wall in said housing, an outer wall at the other end of said housing, said third wall extending between said second wall and said outer wall in spaced relation from said second wall end of said tubular conduit, one side of said third wall defining together with said second wall and said outer wall an inlet chamber in said housing communicating with said impeller inlet passageway, an inlet port in said housing, an outlet port extending through said housing communicating with said recirculation chamber near the upper end thereof, an opening in said second wall communicating with the other side of said third wall, and a recirculation opening in said third wall and in coaxial alignment with said tubular conduit communicating between said recirculation chamseven percent of that of said inlet passageway and three percent of that of said impeller, and the diametrical size of said inlet passageway being approximately 43 percent of that of said impeller.

2. A rapid prime centrifugal pump comprising; a pump housing, an impeller chamber formed near one end within said housing and having input and output zones, a centrifugal impeller rotatably disposed in said impeller with the input zone of said impeller chamber, a recirculation chamben-in? said housing and communicating with the output zone of said impeller chamber, an inlet chamber in said housing and communicating with said other end of said tubular conduit, an inlet port in said inlet chamber, an outlet port extending through said housing and communicating with said recirculation chamber, a partition wall in spaced relation to the other end of said tubular conduit and perpendicular to the axis of symmetry thereof, a circular recirculation opening in said partition wall in coaxial alignment with said tubular conduit and communicating between said recirculation chamber and said inlet chamber, a normally open pressure-actuated shut-off valve in said recirculation opening, said shut-0E valve comprising a body member, a plurality of openings extending end-to-end through said body member, a valve seat at one end of said body member and surrounding said openings at one end, a disc-like valve member, means constraining said valve member to movement in and out of seating engagement with respect to said valve seat, and resilient means normally holding said valve member out of seating engagement with respect to said valve seat, said valve member constraining means comprising a guide member extending centrally through said body member, said valve member being supported at one end of said guide member, and a discdike pressure plate supported at the other end of said guide member and adapted to be acted upon by the force of water flowing through said end-to-end openings.

References Cited in the file of this patent UNITED STATES PATENTS 1,909,517 Bird May 16, 1933 6 Barzen May 19, 1936 Saxe Oct. 13, 1936 Stratton Nov. 30, 1937 Bargen Oct. 3, 1939 Ferguson July 1, 1941 Mueller Feb. 12, 1946 Mueller Feb. 25, 1947 Longenecker May 25, 1948 Jones Oct. 12, 1948 Granberg Feb. 7, 1950 Deters Feb. 14, 1956 FOREIGN PATENTS Great Britain Ian. 24, 1944 

